The embodiments described herein generally relate to a pressurized gas-powered actuator and, more particularly, to methods and structures usable for maintaining an elevated pressure within the actuator, so as to maintain the actuator in a deployed state for a relatively extended period of time.
In pressurized fluid-powered, piston driven actuators, fluid from a pressurized fluid source (for example, a pyrotechnic gas generator) is applied to a piston, thereby producing movement of the piston within the housing, and deployment or extension of an attached piston rod from the actuator housing. In this manner, force may be exerted by the piston rod on an actuatable element located exterior of the actuator housing.
In certain applications of such actuators, it is desirable to maintain the piston in an extended or deployed condition for an extended period of time (for example, up to 15 minutes) after deployment of the piston rod. However, depending on the structure of the piston and/or piston rod, the pressurized fluid may find leakage paths through the interior of the actuator, making it difficult to maintain the piston in a deployed position for an extended time period.
Therefore, a need exists for a structure which seals or traps at least a portion of the pressurized fluid within the actuator so as to maintain the piston rod in an extended condition for the desired extended time period.